On June 27, 1844, Mormon Founder Joseph Smith was murdered

On June 27, 1844, Mormon Founder Joseph Smith was murdered by an angry mob while he sat in a jail cell. The incident arose after Smith ordered the destruction of a news paper that exposed the fact he had married 8 already-married women

“Illinois Governor Thomas Ford proposed a trial by a non-Mormon jury in Carthage, the county seat, and guaranteed Smith’s safety. Smith originally planned on leaving rather than surrendering but when criticized by some followers is reported to have said, “”If my life is of no value to my friends it is of none to myself.”” Smith reluctantly agreed and submitted to arrest, further quoted as saying “”I am going like a lamb to the slaughter; but I am calm as a summer’s morning; I have a conscience void of offense towards God, and towards all men. I shall die innocent, and it shall yet be said of me — he was murdered in cold blood.””
On June 25, 1844, Joseph and Hyrum Smith, along with the other fifteen city council members and some friends, surrendered to Carthage constable William Bettisworth on the original charge of riot. During the trip to Carthage, Smith reportedly recounted a dream in which he and his brother Hyrum escaped a burning ship, walked on water, and arrived at a great heavenly city—foreshadowing their death. Upon arrival at Carthage, almost immediately Joseph and Hyrum were charged with treason against the state of Illinois for declaring martial law in Nauvoo, by a warrant founded upon the oaths of A. O. Norton and Augustine Spencer. At a preliminary hearing that afternoon the city council members were released on $500 bonds, pending later trial. The judge ordered Joseph and Hyrum Smith to be held in jail until they could be tried for treason, a capital offense.
The Smith brothers and their companions were held at the Carthage Jail, joined there by Willard Richards, John Taylor, and John Solomon Fullmer. Governor Ford left for Nauvoo not long after Smith went to stay at the jail. The anti-Mormon “”Carthage Greys””, a local militia, were assigned to protect Smith.
Dan Jones, who was present, relayed to Governor Ford several threats against Joseph Smith made by members of the Carthage Greys, all of which were dismissed as nonsense by Ford.”